Riley RM

Riley RM Series
Overview
Manufacturer	Riley
Production	1945–55
Body and chassis
Class	Executive car (E)
Body style	4-door saloon 2-door open 2 or 3-seater 2-door 4-seater cabriolet
Layout	FR layout
Dimensions
Wheelbase	1.5 L cars – 2.5 L cars –
Length	1.5 L cars – 2.5 L cars –
Width
Height
Chronology
Predecessor	Riley Kestrel body and 12/4 1½-litre engine or 16/4 2½-litre Big Four engine
Successor	Riley Pathfinder

File:Riley 16HP Kestrel (1938) (18751537161).jpg

Riley's 1937-1939 Kestrel body

The Riley RM Series is an executive car which was produced by Riley from 1945 to 1955. Little more than a face-lift of their pre-war 1½ or 2½ Litre Kestrel it was the last model developed independently by Riley prior to the 1952 merger of Riley's still new owner Nuffield, with Austin to form BMC. The RM series was originally produced in Coventry, but in 1949 production moved to the MG works at Abingdon. The RM models were marketed as the Riley 1½ Litre and the Riley 2½ Litre.

There were three types of RM vehicles produced. The RMA was a large saloon, and was replaced by the RME. The RMB was a longer car to carry the larger engine and was replaced by the RMF. The RMC and RMD were limited-production cars, an open 2 or 3-seater and a 4-seater cabriolet. All of the RM vehicles featured the pre-war Riley race developed 1.5 L (1496 cc) 12 hp (RAC Rating) or the successful 1937 new 16 hp (RAC Rating) 2.5 L "Big Four" straight-4 engines with hemispherical combustion chambers and twin camshafts mounted high at the sides of the cylinder block.

Riley RMA

Riley RMA
File:1952 Riley RMA (cropped).jpg manufactured 1952
Overview
Production	1945–52 10,504 produced.
Body and chassis
Body style	4-door saloon
Powertrain
Engine	1.5 L Straight-4 as for 2½-litre Big Four but bore 69mm by stroke 100mm and bhp 60 @5,300 rpm
Chronology
Successor	Riley RME

The RMA was the first post-war Riley. It was announced in August 1945 with the news it would become available in the autumn. It used the 1.5 L engine and was equipped with hydro-mechanical brakes and an independent suspension using torsion bars in front. The body frame (not to be confused with the chassis) was made of wood in the English tradition, and the car featured traditional styling. The car was capable of reaching 75 mph (121 km/h). The RMA was produced from 1945 until 1952 when it was replaced by the RME.

Riley RMB

Riley RMB
File:Riley 2,5-Litre Saloon 1950.jpg
Overview
Production	1946–52 6900 produced
Body and chassis
Body style	4-door saloon
Powertrain
Engine	2.5 L Straight-4
Dimensions
Wheelbase
Length
Width
Height
Chronology
Successor	Riley RMF

The 2.5 L (2443 cc) RMB was a lengthened RMA launched a year later in 1946.

It used the 2.5 L (2443 cc) "Big Four" engine with twin SU carburettors, starting with 90 hp (67 kW) but increasing to 100 hp (75 kW) for 1948 with a 95 mph (153 km/h) top speed.

The wheelbase was longer and the overall length was a full longer. The RMB was replaced by the RMF for 1952.

A car tested by The Motor magazine in 1949 had a top speed of 90 mph (140 km/h) and could accelerate from 0–60 mph (97 km/h) in 16.8 seconds. A fuel consumption of 19.6 miles per imperial gallon (14.4 L/100 km; 16.3 mpg_‑US) was recorded. The test car cost £1224 including taxes.

Riley RMC

Riley RMC
File:1948 Riley RMC Convertible.jpg manufactured 1948
Overview
Production	1948–51 507 produced
Body and chassis
Body style	2-door open 2/3-seater
Powertrain
Engine	2.5 L Straight-4

The RMC (coupé) was an open 2-door, single bench seat, 2/3-seater version of the RMB with a large rear deck area and fold flat windscreen.

Without side windows it was supplied with flexible celluloid-glazed side curtains with a hole for hand signals and, when deployed, flimsy synthetic roofing over a light metal frame. It shared that car's 2.5 L 100 hp (75 kW) engine and could reach 100 mph (161 km/h).

The car was primarily designed for the North American export market, and just over 500 were built from 1948 until 1951. The gear change lever was moved to the steering column on left-hand-drive models.

Riley RMD

Riley RMD
manufactured 1950
Overview
Production	1949–51 502 produced
Body and chassis
Body style	2-door cabriolet
Powertrain
Engine	2.5 L Straight-4

The RMD (drophead) was a traditional 2-door cabriolet, the last cabriolet to wear the Riley name. It used the same 2.5 L 100 hp (75 kW) engine as the RMB, on which it was based. Just over 500 were produced between 1949 and 1951.

File:1950 Riley RMD drop head coupé.jpg dropped cabriolet head A motor car that is a cabriolet has fixed sides to its roof known as cant rails and a folding top that remains part of the vehicle. In a cabriolet like this Riley RMD the tops of the fixed sides, the cant rails, the beams over the side-windows, may be folded along with the top. While the hood is being opened or closed the heavy cant rail beams are supported by exterior hood irons. The hood irons, an elongated S-shape when the roof is up, may be seen at each of the roof’s rear quarters. A more English name for a folding cover or canopy of a (horse drawn) vehicle enabling the occupants to be seen clearly is a "head" or for motor vehicles in the mid-20th century drop head.

Riley RME

Riley RME
File:1953 Riley RME RF.jpg first registered July 1953
Overview
Production	1952–55 3446 produced
Body and chassis
Body style	4-door saloon
Powertrain
Engine	1.5 L Straight-4
Chronology
Predecessor	Riley RMA
Successor	Riley One-Point-Five (1957)

The RME was an updated RMA. It still used the 1.5 L four and featured a fully hydraulic braking system. The body had an enlarged rear window with curved glass.To improve acceleration the rear axle ratio was changed from 4.89:1 to 5.125:1.

When the 2.5 L (2443 cc) car ended production in October 1953 a switch to no running boards was amongst many updates to the RME including wholly new shaped front mudguards apparently from a Mark VI Bentley. See the image below.

Produced from 1952, it was discontinued in 1955 and ultimately its place in the range went in 1957 to the much shorter and unrelated, intended but unused, replacement for the Morris Minor — Riley One-Point-Five or Wolseley 1500.

An RME tested by The Motor magazine in 1952 had a top speed of 75 mph (121 km/h) and could accelerate from 0–60 mph (97 km/h) in 29.5 seconds. A fuel consumption of 24.2 miles per imperial gallon (11.7 L/100 km; 20.2 mpg_‑US) was recorded. The test car cost £1,339 including taxes.

File:1954 Riley RME 1.5 Litre saloon at Capel Manor, Enfield, London, England.jpg

reshaped mudguards all round and no running boards, a 1954 car

Riley RMF

Riley RMF
File:HCVS Haverhill rally BFL637 140713 CPS (11611119984).jpg first registered March 1953
Overview
Production	1952–53 1050 produced
Body and chassis
Body style	4-door saloon
Powertrain
Engine	2.5 L Straight-4
Chronology
Predecessor	Riley RMB
Successor	Riley Pathfinder

The RMF replaced the RMB in 1952. It shared that car's 2.5 L "Big Four" engine as well as the mechanical updates from the RME. The RMH Riley Pathfinder, the last automobile to use the Riley "Big Four" engine, and thus considered to be the last "real" Riley by purists, took its place after 1953 and continued in production until 1957.

Riley 2½-litre Big Four
Overview
Manufacturer	Riley Motors Limited
Also called	Riley 16 h.p.
Production	1937 to 1957
Combustion chamber
Configuration	straight four
Displacement	2.443 L (149.1 cu in)
Cylinder bore	80.5 mm (3.17 in)
Piston stroke	120 mm (4.7 in)
Cylinder block alloy	cast iron, aluminium sump, alloy pistons
Cylinder head alloy	cast iron, hemispherical combustion chambers, spark plugs in centre between valve covers
Valvetrain	90-degree angled overhead valves operated by twin high-lift camshafts moving rockers with short light stiff push-rods powered from the crankshaft by duplex roller chains
Compression ratio	6.9 : 1
Combustion
Fuel system	Twin H4 SU carburettors mechanical petrol pump
Fuel type	petrol
Oil system	pressure fed from sump by submerged gear-type pump driven by skew gear from camshaft
Cooling system	water, thermostatically controlled flow, belt-driven water pump and radiator fan
Output
Power output	106 bhp @ 4,500 rpm Tax rating 16hp
Chronology
Predecessor	none before 1937
Successor	Riley RMH then BMC C-Series engine

Riley RM car models

• Riley RMA 1,5-Litre Saloon 1949.jpg

  Riley RMA 1½-Litre 4-Door Saloon 1949

• Riley RMA 1,5-Litre Saloon 1952.jpg

  Riley RMA 1½-Litre 4-Door Saloon 1952

• Riley Saloon 1949.jpg

  Riley RMB 2½-Litre 4-Door Saloon 1949

• Riley Saloon 1950 2.jpg

  Riley RMB 2½-Litre 4-Door Saloon 1950

• Riley Saloon.jpg

  Riley RME 1½-Litre 4-Door Saloon

• Riley Drophead Coupe.jpg

  Riley RMD 2½-Litre Drophead Coupé 1950

• Riley Drophead Coupe 2.jpg

  Riley RMD 2½-Litre Drophead Coupé 1950

• Riley Drophead Coupe 1952.jpg

  Riley RMD 2½-Litre Drophead Coupé 1952

Modern day support for the Riley RM series; The Riley RM Club

The Club for the Preservation of all Rileys from 1945–1957 If you are already the proud owner of, or are thinking about buying, a Riley RM then this is the Club for you! The Riley RM Club caters for all RM series Rileys (including Pathfinders).

Information on how to join the Riley RM Club can be found at http://www.rileyrmclub.org.uk/index.htm

Find out more about the Club's Heritage Approved spares service along with all other aspects and functions within The Riley RM Club at http://www.rileyrmclub.org.uk/members.htm#spares

The Riley RM Club also has a Facebook page where Riley RM owners share pictures and information about their Cars and the enjoyment they bring.

Scale models

• Meccano Dinky Toys; No. 40a (production 1947–55), Riley Saloon, approximately O scale (1:44).

References

• A-Z of Cars 1945–1970. Michael Sedgwick and Mark Gillies. Bayview Books. 1989. ISBN 1-870979-39-7